Most errors are caused by an omission or an entry error by the user of the software.
If you agree with the notice you received from the state then pay the taxes owed. If TurboTax made a calculation error they will pay any penalties or interest back to you after you pay the state.
See this TurboTax support FAQ for the Calculation Guarantee - https://ttlc.intuit.com/community/charges-and-fees/help/what-is-the-turbotax-100-accurate-calculatio...
What was the Error? Turbo Tax will pay any interest and penalty for a calculation error but not the extra tax due. But it is usually user error, like leaving off some income or entering an amount wrong or in the wrong place. What did the IRS change?
Turbo Tax is a self prepared return. It has no way of knowing or checking that you entered something wrong or in the wrong place or entered something twice Or left something out. It doesn't check against any outside sources. The IRS and state has copies of all the W2s and 1099s your employer and banks/brokers, etc. sent in to match against. Turbo Tax only checks the calculations of what you entered. It is your responsibility to check it over before you file. They only Guarantee that the calculations are right based on the entries you made.